This guide will not attempt to be complete, but will focus on a few important or interesting  facts, and of course, my own somewhat questionable opinions. As for my opinions, it might interest you to know something about me. I have been playing clarinet and sax for, well, several decades. I'm not a professional, but a good enough amateur to be in some demand, and have had opportunities to play in a variety of concert bands, swing bands and combos. I have had the opportunity to play a variety of vintage saxes and own several. I have enough technical expertise to do minor repairs such as pad replacement, replacing corks on clarinet tenons and sax necks, and minor adjustments for those unavoidable leaks that appear from time to time. Major work I leave to a pro. In other words my opinions are not without foundation, but should not be considered gospel.

I'll begin by saying that playing a vintage sax should be done from love, and not solely because a professional level horn can be obtained for a few hundred dollars.  These older horns have their quirks - and they are many decades old. Repair parts may be hard to find. The keywork may be sloppy and difficult (or impossible) to adjust to modern standards. Intonation will be a bit different. But boy! - they can sound great. A young player won't have developed the technique to take advantage of the great vintage sound but will have all the disadvantages of an old horn, so I don't consider vintage instruments to be good choices for beginning students. On the other hand, it can be great fun for a moderately experienced player to work with one of these, and the sound is a bit different from modern horns.  It's hard to describe but rewarding .

Why should a saxophonist consider purchasing and playing a vintage instrument? I can think of several reasons, and I'm sure there are many more. First, players who are interested in older music may prefer the authentic period sound of a vintage sax, and players who particularly like the sound of a certain artist may want to have a sax similar to one played by that artist. Second, saxes constructed to professional standards are available for far less than a modern instrument of similar quality. Next, many of the older saxes look different. Some are silver plated, some are gold plated (over silver) and look quite elegant. Others were bare brass, and tarnished brass looks the opposite of elegant. Either look may be appealing. Finally, there's just something about playing an instrument that's older than you are.

If you are seriously considering a vintage sax, whether a particular instrument or in general, you should do as much research as you can stand. That will help you to become aware of the the peculiarities of different instruments and what features are liked and disliked by knowlegable players. There are excellent sites like www.saxpics.com and saxgourment.com, to name only two, and there are many forums that you'll find if you perform a search on a particular sax. One word about forums, listserves and message boards: Many have some knowlegable and experienced players who offer valuable information and opinions. Unfortunately, many of the most vocal members tend to be high schoolers with a year or two of experience who think they are knowlegable. It can be hard to tell the difference, but anyone who says that a particular sax is absolutely the best, or who is equally decisive about anything, is suspect. Most experienced folk know that, when it comes to vintage horns, there are too many variables for anything to be absolute. They'll tend to talk about their favorites rather than "the best".

Brand Names
There were several major manufacturers of quality saxophones in the first half of the 20th century.  All have their devotees and detractors. The most common American instruments are Buescher, Conn, Holton, King (by H.N.White) and Martin. French manufacturers include Selmer, Buffet, Cousenon, and Dolnet. Occasionally one will see an instrument made by A. Sax, the company begun by the French inventor. Kohlert and Keilwerth are early German makers. You can find out a lot about these and other manufactures  by searching the internet.

Many other brand names will be seen. Most are stencils.  It was a common practice, especially for Busecher, Conn and Martin to manufacture a horn for other companies to engrave or 'stencil' with their own company name. At times these stencil models were of a somewhat lower quality, lacking features such as rolled tone holes or special auxiliary keys. Others are virtually indistinguisable from the manufacturer's brand. Wurlitzer is a common brand name that appears on stencils, as is Olds in that era. York made some of their own instruments, but most are stencils.

The most respected name in modern saxophones is Selmer (Paris), but in the first half of the last century, even Selmers (before their Model 22) were stencils - mostly Conns until the 1920's, often engraved 'Geo. M. Bundy'. The early 'Bundy' (as opposed to 'Geo.M. Bundy') models were mostly Bueschers (and Selmer eventually bought Buescher in 1963). Martin, Holton and Keilwerth manufactured models for Selmer, as well.  The Model 22, and several later saxes appear to be based on earlier A. Sax  models but were probably made by Selmer (Paris). In my opinion, early Selmers - before the Model 22 - tend to be overpriced, as buyers see the Selmer name and don't understand that they are buying a stencil from another manufacturer.
 
Limitations and Pitfalls
By modern standards, the keywork on the earlier saxes, by whatever manufacturer, will not be as slick. Partly that's because the designs just aren't as advanced, but don't forget that these instruments are old and worn.  Intonation is an issue as well. Despite the protests of devotees of particular instruments, no instrument can be perfectly in tune. On vintage instruments some notes are likely to be more sharp or flat than on quality modern horns.  With the right mouthpiece, most can be played well, but you may have to experiment with different setups (mouthpiece, reed and ligature combinations) and will you have to become accustomed to playing a particular horn.

Vintage professional saxes are well built, but any instrument will need service from time to time. Good technicians are hard to find, and good technicians that are familiar with vintage instruments are even rarer. If you know a decent technician, ask him (her) what instruments he (she) is comfortable working on. Have a real discussion, and get some information on what features the tech knows about. Then read a little and see what other experts say on their web sites and on forums (note my earlier warning about forums). If you find a tech who genuinely likes a particular vintage sax, you should consider that a strong advantage for that type.

Having recently moved, I tried a new tech who gave me a good pitch about how much he liked my old Martin tenor. I had him check the sax for problems and do a repad. When he had completed the work, the sax was unplayable. There was a leak at one of the soldered tone holes that Martin is famous for. He eventually fixed it and it plays very well, but the solder job on the tone hole is a mess. Any tech who knows anything about Martins knows about those tone holes, as you'll see if you do any research on those fine instruments, but he didn't. I should have found that out in my conversations with him beforehand. Lesson learned.

I've mentioned intonation a couple of times. For all players, but particularly those of us with vintage instruments, I highly recommend using an inexpensive electronic tuner like the Korg CA-30 as an aid. Don't just tune a single note - check every note on the instrument. Stop in the middle of practice to check on the notes that tend to be most out of tune. Eventually you'll learn to compensate for the quirks of your instruments and you'll develop a better ear, too. I particularly love to try this with players who have the very best modern instruments - they're invariably shocked at how out of tune they are. If you just can't get in tune, try a different mouthpiece. Most vintage mouthpieces have a larger chamber and tend to play lower in pitch than modern pieces - especially modern student mouthpieces. So, if you're tending to be too sharp, and pulling the mouthpiece out doesn't fix it,  look for a large chamber mouthpiece.

One type of instrument that can't be played in tune is an instrument marked 'high pitch". Before the 1930's, there was no single standard as to what pitch was an A, a B, or an F#, etc. Different groups tuned to different standards ranging from A in the 430's to A in the 450's. Things settled out into a two factions: a still not standardized high pitch in the 450's vs. a standardized A=440 (low pitch) which became the modern standard.  Saxes and other instruments made in the early 1900's are almost always marked as Low Pitch or High Pitch (often LP or HP). I have heard stories of  individuals who have a high pitch Tenor that can be played as a B (rather than a B flat) instrument, and rumors of high pitch Altos that can be played as an E (rather than E flat) alto. I have played a few high pitch saxes, but never one that was a full half step high. For the most part they are considered useless. Professional sax players can certainly play in any key, but for those of  us who are uncomfortable with six or seven sharps or flats there would be an advantage to having an E alto or a B tenor, as it would be much easier to play with guitars that often work in those keys. If you have the time and money to try and find a really high, high pitch instrument, be my guest.  Just don't get your hopes up.

There is a type of sax that does offer some advantages for playing with bands that play regularly in the sharp keys, and that is the C melody sax (also called a C tenor).  These were manufactured up to about 1930, primarily for the home market.  Pitched in C, they play a step above a Bb tenor and a step and half below an Eb alto.  For many years these instruments were regarded with scorn, and are still so regarded by many knowlegable saxophonists - for several reasons.  Concert bands, marching bands and orchestras do not have parts for saxes in C.  Accomplished sax players can play in any key and commonly learn to transpose, on sight, from music written  in C (the piano or vocal part), so they don't need a sax pitched in C.  Since the bore of the C melody is similar to an alto, but the length is closer to a tenor, the sound tends to be smaller or thinner -  a concept that is hard to describe in words.  Finally, like other vintage saxes, a C melody sax may require experimentation before one finds a setup that will allow sax play in tune. There are special C melody mouthpieces, both vintage and of modern manufacture, but many people prefer the sound when played with alto or tenor mouthpieces. I think C melody saxes are great fun, and I have published a separate guide for them. They aren't for everyone, though, and especially not for beginning players.

Finally, if you play in a group with folks who all play shiny modern instruments you may have to overcome some predjudice if you show up with a vintage instrument. Surprisingly that's likely to be more of a problem with young players who are playing something less than professional quality instruments, as they tend to be more concerned with appearances. More mature players who have worked their way up to professional level instruments are more likley to be impressed with sound and performance, but you can certainly run into snobs at any level.

Advantages
For me, the two advantages that count are the sound and the cost. Since the introduction of the Selmer Mark VI, arguably the best sax ever made, modern saxes have been designed to have a brighter, edgier and more penetrating sound. On some instruments it works amazingly well, and some music fits that type of sound. Vintage saxes tend to have a darker, mellower and (dare I say) sexier sound. I love it, and for playing in swing bands and jazz combos, I think it's preferable. I should note that some modern horns, like the Mark VIs, some Keilwerths, and I am sure, many others, are quite versatile and capable of producing that kind of sound, but many are not.

Since you are looking on E-Bay for information on saxes, I suspect that cost is a major factor. The versatile modern saxes I referred to in the previous paragraph are expensive. A quick search will show that a Mark VI in good condition will cost at least $5,000 - often much more. Used Keilwerth and SML saxes will go for less but still several thousand for one in good condition. Vintage Conns, Martins, Kings, Bueschers and Holtons are considerably less expensive, usually less than $1,000, although instruments offered by musicians who have actually been playing them and who will vouch for them may still cost $1,000 to $2,000. Really special examples may fetch more but really high cost examples often have no bidders, because they are overpriced.

C-Melodies are at the bottom end of the price range for vintage professional instruments, with altos slightly to much more. Tenors and sopranos cost more yet and the big baris tend to be most expensive among horns of similar quality.

E-Bay Hints and Warnings
Using the categories Musical Instruments >Woodwind > Saxophone > Vintage (Pre-1980) is a good place to start looking. When you search use "sax*" to catch both sax and saxophone as well as all the many misspellings. Similarly use "bari* sax*" if you are looking for a baritone saxophone. "Vintage" is a good search term as are "old" and "antique".

What is it? Many listings simply say sax or saxophone, with no mention of alto, tenor, etc. Be especially careful if it looks like a tenor with the double curve in the neck. A C Melody is proportionately very similar to a tenor, but smaller. The difference in size won't be obvious since the proportions are so similar. Even if the sax is listed as a tenor, you should make sure it's not a C Melody. A few sellers might lie to you, but most simply don't know the difference, so it's up to you to determine. My guide on C Melody saxes has more information on how to identify them, but the best method is to ask the seller the length of the sax from the bottom of the bend to the top of the tube, without the neck. 21" or so is an alto, 24" a C melody and 27" or more a Tenor. Sellers will usually tell you the truth, since it's so easy to verify the measurement when you receive the instrument.

How old is it? If the seller doesn't provide it, ask for the serial number. X's for the last three digits (456,xxx) is ok if the seller is suspicous of your motives. Google "martin sax serial" or "conn sax serial" to find one of the many serial number lists that will tell you the approximate date of manufacture. Be careful, as some companies reused serial number sequences at different periods. Once you have a tentative date, go to saxpics.com to see pictures of the models that were made at that time and compare them to the sax you are considering. Note that European serial number lists prior to WWII, especially for German companies, may no longer exist.

Be sure it's a low pitch instrument if it dates in the 1930's or earlier.

Older saxes have keyguards made of brass rod, while newer models use sheet metal. There may be exceptions.

Know about second line instruments. Conn also made Pan-American as a second, lower quality line, as Martin made Indiana, Buescher made Elkhart and King made Cleveland. Some of the second line brands were originally separate companies, purchased and then retained as the second line brand. The second line saxes lacked some features of the professional models, and in some cases may have been made of lower quality materials. Sometimes they were made on the tooling for an older line of the professional model after a new professional model was introduced. Generally, they are quite competent instruments and a decent value for a hobbiest if you can find one in good condition.

Know about stencils. Wurlitzer, York, Lyon and Healy, and Silvertone are usually, if not always, stencils. Other unrecognized names may be as well, since there are dozens if not hundreds of companies who resold stencils. They range from the larger companies like Wurlitzer to indiviual music stores. Although they may be indistinguisable from the manufacturers own instruments, except for the engraving, you should consider them to be similar to the second line instruments unless you have reason to believe otherwise, either from information provided by the seller or from your research. Serial numbers may or may not correspond to the manufacturer's numbering. The different manufacturers' saxes have particular characteristics that will help you identify their stencils. Conn made saxes have a key guard on the lower right side of the sax that resembles the three point Mercedes star, and serial numbers on most Conn made stencils begin with a "P", like their Pan-American instruments. Martins have toneholes that are soldered on (not obvious) and beveled at the top (more obvious). The fitting that holds a lyre (music holder) are pretty distinctive, too.

Many French, German and other European manufacturers made quality instruments. Among the names are Buffet, Cousenon, Dolnet, Kohlert, Selmer and of course Adolphe Sax. Aside from Selmer, I don't know enough about these to offer any advice, but information is out there if you're interested.

Rare? Probably not. Some sellers use this term in almost every description they post. To me it simply suggests that a seller may not constrained by facts. Sometimes, of course, an instrument really is rare, and in such cases, the seller will explain why. If it's just a word in the title, I consider it a warning rather than an advantage.

Condition? Expect to have the sax serviced when you get it. Most sellers who regularly sell instruments will now suggest that, but the casual seller will often say that a sax looks like it's in good condition. Most will claim to know little about the instrument, possibly to avoid blame in case it turns out not to be as described. Unless the seller says he(she) has played the instrument and it is fully functional, or the seller is a repair shop that has serviced the instrument, you should expect that the pads will need to be replaced and the sax will need some adjustment. That will add at least $200 - probably more - to the cost of the sax. Find a technician before you buy a vintage sax and find out the rate for services. Get prices to replace several pads, to completly repad and adjust, and to fully overhaul a sax. The prices will be different for altos and tenors, etc. Most techs will be reluctant to quote a specific price for a complete overhaul, as the amount of work can vary tremendoulsly. You may be able to pursuade them to give you a non-binding general idea. It might also be possible to find out if the tech has any old horns from which parts can be scavenged. If you buy a sax that needs a part, it can be very expensive to find a replacement or fabricate one.

Like new? Why would a sixty year old (or older) sax be like new? Was it never played? There should be a story to go along with this.

No neck? Forget it. Vintage necks are not available, and custom neckscost hundreds of dollars.

I fear this guide may sound discouraging. That was certainly not my intention. Most instruments are as described, and good bargains can be found. You just need to know enough to avoid major problems. Vintage saxes can be a treat to play and you'll be glad you've saved one from the attic or closet and put it into use. Good luck.